This disclosure relates to systems and methods for improving the ability to pack wheels and other vehicle components when a human-powerable wheeled vehicle is not being ridden. Examples of human-powerable wheeled vehicles include unicycles, bicycles, tricycles, quadricycles, wheelchairs, strollers, and vehicles such as electric bikes and mopeds that can use human power in addition to other power sources.
Wheeled human-powerable vehicles typically use a space frame structure because this provides high strength and stiffness for minimal weight, but space frame structures can result in a shape that takes more space than desired when stored or transported. Wheels that comprise a rim, a hub and steel spokes in tension between the hub and the rim are one example of a space frames structure that is difficult to pack because there is a conical bulge and axle in the wheel (and hub) center. It is difficult to pack two assembled wheels having these conical centers and axles together into a small space. However, prior to the wheel being assembled, the unassembled spokes, rims, tires, and hubs (with axles) take up little space.
Wheeled human-powerable vehicles are not always ridden. They are also transported over significant distances by other vehicles such as cars, public transit (buses, trains, etc), airplanes, boats, or other modes of transport. These human-powerable vehicles might also need to be hand carried over rough terrain or in an airport, bus terminal, or train station. In these situations, it is beneficial for the vehicle to be compactly packed, protected from other luggage, and covered in a way that protects others from any sharp or dirty elements of the wheeled human-powerable vehicle. Additionally, these human powerable vehicles can be stored and locked more easily they were in a more compact configuration.
One specific example is the transport of bicycles on commercial aircraft. In the past, airlines allowed passengers to check bicycles at no extra charge and even supplied bicycle boxes. Now many airlines charge for each piece of checked luggage. They charge even more for items that are oversize (length+width+height is greater than 62 linear inches) and/or overweight (typically over 50 pounds). If not properly packaged, the airline might refuse to take a bicycle or similar item that doesn't look like a suitcase or duffel bag. This creates a financial incentive to have a bicycle (or any other wheeled human-powerable vehicle) that can be packed within the 62 linear inch limit and weighs as little as possible.
There are bicycles that use small wheels and tires (20 inch or less), but bicycles with small wheels generally don't perform as well on a variety of road surfaces and terrain as bicycles with full-size wheels. For adult bikes, full-size wheels can be defined as wheels with tires nominally 24 inches in diameter or greater and small wheels have tires nominally 20 inches in diameter or smaller. Here is a list of common small and full wheel and tire sizes:
Common name(nominal outsideBead seat diameterdiameter of tire)Outside diameter of rim(inside diameter of tire)700C/29 inch  648 mm (25.5 inches)  622 mm (24.5 inches)  650B/27.5 inch610 mm (24 inches)584 mm (23 inches)26 inch585 mm (23 inches)559 mm (22 inches)24 inch533 mm (21 inches)507 mm (20 inches)20 inch477 mm (19 inches)451 mm (18 inches)20 inch  432 mm (17.75 inches)  406 mm (16.25 inches)16 inch  375 mm (14.75 inches)  349 mm (13.75 inches)
Some bicycles with small wheels use ingenious methods for folding the bike to convert from a compact configuration to a ridable configuration quickly, cleanly, and without the use of special tools. Some folding bicycles with small wheels can fold small enough to fit into a rectangular volume that meets the airline checked luggage 62 linear inch size requirement and the 50 pound weight limit. It's much easier to fit into 62 linear inches when the wheel is less than one third of the total length+width+height, which is what occurs when the nominal outside diameter of the tire is 20 inches or less.
There are bicycles with full-size wheels that can fit within airline 62 linear inch size requirements for normal checked luggage, but these bicycles require time, tools, and expertise to disassemble and reassemble. Packing these bikes with full-size wheels into 62 linear inches is difficult. Referring to the previous list of bike wheel sizes, a typical road bike uses 700C wheels, which have an outside diameter of the tire of between 28 and 29 inches and an outside diameter of the rim of approximately 25.5 inches. Thus, the typical suitcase for these bikes is 26×26×10 inches. It takes removing the air from the tires, many disassembly steps, detailed instructions, tools, and patience to work out how to get all of the parts to fit into a case having these dimensions.
One problem with trying to fit a bike with full-size wheels into the airline maximum of 62 linear inches, is that the wheels are both large in diameter and fat in the center due to the use of tension spokes in a triangular configuration when looked at in cross section or a conical configuration when viewed three dimensionally. The spokes typically terminate in a set of holes in one plane in the rim and terminate in two parallel planes in a circular configuration in the hub. When looked at in cross section this looks like a triangle that is wide at the hub and narrow at the rim. When two wheels with fat centers are put into a 26×26×10 case, there is almost no room for anything else. Any space that can be saved by having the wheels stored more compactly could simplify the task of packing the other parts of the bicycle and might mean that the rest of the bike doesn't need to be disassembled as completely. It is known to have wheels that are disassemblable to save space, but these disassemblable wheels typically do not use spokes in tension in a triangular/conical configuration. Wheels using spokes in tension in a triangular/conical configuration are desired because this configuration because this space frame configuration has a high strength to weight ratio. Because weight is paramount for a human-powered vehicle, the vast majority of bicycle wheels have spokes in tension in a triangular/conical configuration.
Many bicycles that are transported as checked luggage require a structural case. These cases add to the total weight of the luggage. There is also the issue of what to do with this case when one arrives at a destination and wants to start riding the bicycle. It is better if the bicycle can be configured in a compact arrangement and require minimal or no external container used solely as a suitcase. If the bicycle can be its own suitcase, this would be ideal.
To summarize, it is desired to have a system and method for packing a human-powerable vehicle that is (a) is as lightweight as possible and (b) minimizes the space needed. Such as system would likely use spoked wheels, which can be bulky to pack if built using conventional hubs. Ideally, such a system (c) would not require the use of a separate structural suitcase to transport the tires and/or tires and bicycle frame.
It should be understood that the drawings are not necessarily to scale. In certain instances, details that are not necessary for an understanding of the invention or that render other details difficult to perceive may have been omitted. It should be understood that the invention is not necessarily limited to the particular embodiments illustrated herein.